Means for stirring glass



Jan. 1, 1924 C. A. PARSONS MEANS FOR S'TIHRING GLASS Filed Oct. 17.1922. 2 SheetsSheet 1 Jan. 1, 1924 C. A. PARSONS MEANS FOR STIRRINGGLASS Filed Oct. 17 1922 2 Sheets-Sheet 2 //WENTO/?.- HAQLEsA. PAQSONS,

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Patented Jan. 1, 1924.

UNET $TATS CHARLES ALGERNGN PARSONS, OF NEWCASTLE-ON-TYNE, ENGLAETB.

rims rim s'rmnma GLASS.

Applleaflon fled October 17, 1922. fierlal 595,139

To all whom it may concern Be it known the: i, Cniuuirs AUIIERNONPAnsons u a subject. of the King of Great Britain and Ireland, andresiding at Heston W'orks. Ne'wcastle-on-Tyne, in the county ofNorthumherlanll England. have invented certain new and usefulImprovements in and. Relatim to the Means for Stirring Glass, of whichthe following is a spec-ifica tion.

This invention relates to improvements in the manufacture of glass andmore particularly to the stirring of optical glass,

According to the usual process adopted at the present time, opticalglass is melted in clay pots which are often formed with an integral tophaving a side opening or mouth through which the ingredients areintroduced: When a pot has been filled and has been heated for esufiicient period at a high temperature to incorporate thorou hly allthe ingredients and lo allow air bu bios to rise to the surface thetemperature is gruduully lowered and the glass well stirred by acylindrical lay stirrer actuated by u watencoole l her or tubeintroduced through the mouth of the pot. The stirrer, which ismaintained in :1 substantially vertical posi lion. moved by hand or moregenerall by mechanical gmwer in a more or less circular orhii. of anypreterniineil shape and posion. The speed of motion of the stirrerhowever, limited, for if too great, air is entrained in the Wake of thestirrer and in consequence of this limitation the stirring is Found inpractice to he insufficient to secure complete ll'fflllfifltlfllly ofthe glass.

The object of the present invenlion is co remove this limitation and losecure a much more thorough st rring of the glass than herri tiforewithout the entrainment of air. or in other words, to enable a muchgreater power to he applied in the process of stirring.

With this object:-

The invention consists in imparting to the stirrer a rapid rotary motionabout its own axis with or withou r: relatively slow orbital movement.

The invention also consists in a stirrer of the hind set forth in thepreceding puregrapz; constructed from a simple or complex loop of metaltube.

The invention likewise consists in the ii proved form of stirrershereinelter described or indicated.

Referring to the accompanying dr in igure 1 shores an elevation for themost part in section, of a form of peddle stirrer and driving mechanismtherefor,

Figures 2 and 3 being corresponding side and end views respectively, and

Figure 4 a section on the line l-- of ig-- ure 1 as seen in thedirection of the arrows; While Figure 5 shows a modified form of theinvention in which a loop-formed stirrer is em iloyed,

i igures 6 and "i being corresponding side and end views respectively.

W'here desirable corresponding parts in the diflenent forms of theinvention are indicated by the same reference symbols.

In carrying the invention into ell'ect according to the form shown inFigures 1 to 4, the clay stirrer. a, is of the usual cylindrical shapebut provided with projections or paddles, b, which may be arranged inspiral formation as shown, the diameter of the stirrer at the pointwhere it passes through the surface of the glass being as small possibleconsistent with strength, so as to reduce the disturbance at this pointto s minimum, The stirrer may be actuated in the usual manner from awater-cooled iron tore r. to which, according lo the present invcntiom arotary motion is imparted by here} gear a, a, in lhe water-cooied heedol the stirring rod or tube. This head. may comprise a chamber, 0,provided on rheone hand with a tubular extension, 1. serving f r theaccommodation of the driving' shaft, 11. and the water outlet, and onthe other hand ith a cap, 1' to which ihe water inlet pipe, 7r, issecured. Passages. m. are also formed in the cup, i, to serve as aninlet for the cooling water A hollow shaf 71 to which the stirrer properis attached, is cooled in the manner shown by an inner tube, 0, arrangedin a space, 7*, of larger diameter so as to leave an annular recess forthe return flow which finds an outlet by way of the aperture, 8,registering with. a similar aperture, t in a sleeve, u, surroundin theshaft, 11, and driven from one of the vol wheels, (2 by a pin, 1;, thesleeve, u, serving as shown to take the weight of the stirrer itself.The course of the cooling water is indicated by the'arrows, and it willbe seen that after entering through the pipe, is, and passages, m, inthe cap, 2', it asses down the centre tube, 0, and returns t rough thesurrounding annular space and by way of the apertures, a and t, to theinterior of the chamber, e, and thence through the outlet passages, inthe cap, i, to the annular space formed by the clearance between thetube, 1, and the driving shaft, h.

In order to attach the stirrer proper, its head, '2'", is formed ofsquare shape to correspond with a square box or socket, m, attached tothe shaft, n, a clip, 2, being provided to engage beneath the shoulder,2, of the square head of the stirrer so that it may be attached to thebox, 00.

Alternatively, the stirrer, a, may be made entirely of clay and actuatedfrom a water cooled socket rotated by any suitable means Instead of theclay stirrer described above, a water-cooled stirrer made of a suitablemetal such as steel may be used. Such a stirrer may be of any suitableform, but generally, as shown in Figures 5 to 7, I prefer to constructit as a more or less helical loop, 3, of solid drawn steel tube, the twoends of the loop being brought close together as shown in Figure 5 andinserted into the end of the shaft, n, near the surface of the glass soas to secure a low velocity of motion at this point, while the loop. iswide below so that the tube may move with a high linear velocity in thebody of the glass. The shaft, n, is provided as shown in Figure 3, withducts 4 and 5 for the circulation of the cool ing water, the course ofwhich will be evident" from the arrows without further description.

The mechanism for rotating the loop may conveniently be the same as thatalready described in relation to the clay paddle.

The complex form of loop illustrated is well adapted for securing athorough mixing of the upper and lower layers of the glass. but in somecases the loop may be of simpler form and lie in one plane.

Inorder to secure the best results, the stirrer in addition to a motionof rotation about its own axis is also given a slow orbital movement byany. convenient mechanism such as is now employed or otherwise.

The general design of the stirrer whatever its precise form is such asto secure the maximum strength for the transmission of the greatestamount of power for the eflec' tual stirring of the glass.

Although I have described certain forms of the invention in detail byway of illustration of its general character, I wish it to be understoodthat I do not. restrict myself to such specific forms, as the latter canbe modified to a large extent without exceeding the scope of theinvention.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent is 1. For use in the manufacture of glass, astirrer with means for giving thereto a rotary motion about its own axisand an orbital movement, substantially as and for the purposesdescribed.

2. A stirrer as set forth in claim 1, including a loop of metal tube,substantially as described.

3. A stirrer as set forth in claim 1, including a loop of metal tube, inwhich cooling water is circulated through the loopformed stirrer,substantially as described.

4. Driving mechanism for a stirrer as set forth in claim 1, comprising achamber bevel wheels within the chamber and a passage for thecirculation of cooling water passing through one bevel wheelsubstantially as described.

In testimony whereof I have signed my name to this specification.

CHARLES ALGERNON PARSONS.

